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Aluminized steel sheet combines the
strength of steel with the advantages of aluminum, and is
extensively used for the parts that need heat resistance;
such as automobile exhaust systems, and appliances.
Aluminized steel becames commercially
available in the 1950's. Similar to the galvanizing process,
aluminum is metallurgically bonded to the steel surface, providing
excellent heat reflectivity and corrosion protection.
Aluminized Steel (ASTM-A463) is hot-dip coated on both
sides with an aluminum/silicon alloy coating? This steel has the
surface characteristics of aluminum with the superior strength and
lower cost of steel. It is produced with a soft, satin-like finish.
Aluminized steel is manufactured in two grades. Type 1 has a Si-Al
alloy coating and is best suited in an environment where a
combination of heat and corrosion is involved. Type 2 has
a pure Al coating and has excellent resistance to atmospheric
corrosion.
Aluminized steel is carbon steel with a thin coating of aluminum to
resist rust. This is the same material automobile mufflers and tail
pipes are made of and has a long record of good service in high
temperature applications.
Aluminized Type 1 resists heat and oxidation up to 900°
F (482° C) without discoloring and
maintains its strength at temperatures up to 1250°
F (677°C).
Aluminized Type 1 can be a cost effective alternative to stainless
steel since it frequently maintains its appearance better in service
than 409 stainless.
Aluminized Type 1 has excellent heat reflectivity during exposures
below 900° F (482°
C), reflecting up to 80% of the radiant heat that strikes it.
Aluminized has superior performance compared to galvanized for
resistance to atmospheric, salt spray and muffler condensate
corrosion.
An outstanding example of how effectively aluminized Type 1 combats
the combined attack of heat and corrosion is the automobile muffler.
On the inside, mufflers are exposed to intense heat, and on the
outside, they are splashed with water, mud and snow melting
chemicals.
Consumption of aluminized steel in North America is approximately
700,000 tons. |
